SOLUTION: A circular patch of oil spread out on water increases at a rate of 6 cm^2/s. at what rate is the area increasing when the radius is 2cm?

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Question 1056291: A circular patch of oil spread out on water increases at a rate of 6 cm^2/s. at what rate is the area increasing when the radius is 2cm?
Found 2 solutions by Fombitz, Alan3354:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
For a circle,
A=pi%2AR%5E2
So,
dA%2Fdt=2pi%2AR%2A%28dR%2Fdt%29
Substituting,
6=2pi%2A2%2A%28dR%2Fdt%29
dR%2Fdt=6%2F%284pi%29
dR%2Fdt=3%2F%282pi%29cm%2Fs

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A circular patch of oil spread out on water increases at a rate of 6 cm^2/s. at what rate is the area increasing when the radius is 2cm?
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You state that the area is increasing at 6 cm^2/s.
Then you ask for the rate of increase of the area.
You just said it's 6 cm^2/second.